Icariin alleviates murine lupus nephritis via inhibiting NF-κB activation pathway and NLRP3 inflammasome

Aims: Lupus nephritis (LN) is a kidney inflammatory disease caused by systemic lupus erythematosus (SLE). Both NF-kappa B activation and NLRP3 inflammasome activation are implicated in LN pathogenesis, suggesting they are potential targets for LN treatment. Icariin, which is isolated from Chinese medicine Horny Goat Weed (Ying Yang Huo), has been shown to have anti-inflammation activity, and inhibit activations of both NF-kappa B and NLRP3 inflammasome. In present study, the effects of icariin on LN were evaluated in MRL/lpr mice. Main methods: We treated MRL/lpr mice with icariin for 8 weeks and then analyzed the renal function and kidney pathology. We monitored the levels of anti-dsDNA antibody and the deposition of immune complex after icariin treatment. We also detected the macrophage infiltration, NF-kappa B activation, NLRP3 inflammasome activation and inflammatory cytokine TNF-alpha production in MRL/lpr mice after icariin treatment. Key findings: We found that MRL/lpr mice treated with icariin displayed significantly attenuated the renal disease. Icariin-treated mice showed significantly reduced serum anti-dsDNA antibody level and immune complex deposition. Icariin inhibited NF-kappa B activation and TNF-alpha production in MRL/lpr mice. Icariin inhibited CCL2 production and macrophage infiltration in MRL/lpr mice. Finally, icariin suppressed NLRP3 inflammasome activation and IL-1 beta production in MRL/lpr mice. Significance: Icariin alleviated murine lupus nephritis via inhibiting NF-kappa B activation and NLRP3 inflammasome activation.